BJOG Exchange
Risk of colorectal cancer in women with pelvic inflammatory disease: a matched cohort study
Sir, I read with interest the article by M-I Hsu and H-W Lin.1 Although the hypothesis is plausible, the methodology is seriously flawed, making the results meaningless. The diagnosis of pelvic inflammatory disease (PID) was made based on the women’s medical history, clinical features at presentation, findings on bimanual palpation, findings of ultrasound scanning, culture of vaginal samples and laboratory data. The authors stated that they ensured the validity of the PID diagnosis by including only women who had at least two consensus diagnoses of PID. In addition, they excluded those who are younger than 13 years and older than 45 years of age, assuming they are at lower risk of PID. The British Association for Sexual Health and HIV (BASHH) guidelines for the management of PID emphasise that the PID symptoms (e.g. bilateral lower abdominal pain) and signs (e.g. bilateral lower abdominal tenderness and pyrexia) are all suggestive of the diagnosis but not confirmatory. The clinical symptoms and signs lack sensitivity and specificity.2 The positive predictive value of a clinical diagnosis could be as low as 65% when compared with laparoscopic diagnosis. Furthermore, laboratory tests such as elevated ESR or C-reactive protein may support the diagnosis but are not specific.2,3 Even the presence of endocervical or vaginal pus cells is non-specific, with a poor positive predictive value of only 17%.4 The diagnosis of PID can only be confirmed with a positive bacteriological testing for lower genital tract infection such as gonorrhoea or chlamydia.2,3 Having two consensus diagnoses of PID based on non-specific features does not improve the validity, nor could the diagnoses be achieved with certainty in
the context of a retrospective study based on reviewing a database. Moreover, the authors relied on vaginal swabs, which mainly diagnose Gardnerella vaginalis and anaerobes. None of the women included in this study underwent endocervical swabs for Chlamydia trachomatis or Neisseria gonorrhoea.3 It is understandable when the suspicion of PID is raised that empirical antibiotic treatment should be considered, particularly in sexually active women 12 visits was 2.84 (95% CI 1.04–7.80,
1449
Risk of colorectal cancer in women with pelvic inflammatory disease: a matched cohort study
Sir, I read with interest the article by M-I Hsu and H-W Lin.1 Although the hypothesis is plausible, the methodology is seriously flawed, making the results meaningless. The diagnosis of pelvic inflammatory disease (PID) was made based on the women’s medical history, clinical features at presentation, findings on bimanual palpation, findings of ultrasound scanning, culture of vaginal samples and laboratory data. The authors stated that they ensured the validity of the PID diagnosis by including only women who had at least two consensus diagnoses of PID. In addition, they excluded those who are younger than 13 years and older than 45 years of age, assuming they are at lower risk of PID. The British Association for Sexual Health and HIV (BASHH) guidelines for the management of PID emphasise that the PID symptoms (e.g. bilateral lower abdominal pain) and signs (e.g. bilateral lower abdominal tenderness and pyrexia) are all suggestive of the diagnosis but not confirmatory. The clinical symptoms and signs lack sensitivity and specificity.2 The positive predictive value of a clinical diagnosis could be as low as 65% when compared with laparoscopic diagnosis. Furthermore, laboratory tests such as elevated ESR or C-reactive protein may support the diagnosis but are not specific.2,3 Even the presence of endocervical or vaginal pus cells is non-specific, with a poor positive predictive value of only 17%.4 The diagnosis of PID can only be confirmed with a positive bacteriological testing for lower genital tract infection such as gonorrhoea or chlamydia.2,3 Having two consensus diagnoses of PID based on non-specific features does not improve the validity, nor could the diagnoses be achieved with certainty in
the context of a retrospective study based on reviewing a database. Moreover, the authors relied on vaginal swabs, which mainly diagnose Gardnerella vaginalis and anaerobes. None of the women included in this study underwent endocervical swabs for Chlamydia trachomatis or Neisseria gonorrhoea.3 It is understandable when the suspicion of PID is raised that empirical antibiotic treatment should be considered, particularly in sexually active women 12 visits was 2.84 (95% CI 1.04–7.80,
1449
